Thermostatic valve with by-pass



Jan. 14, 1930., w. L. DAVIS ETAL THERMOSTA'IIG VALVE WI ETH BY-PASS Filed March 9., 192a M ,w, e W #7 w QM 3, K a! Q w x w a 4 WILLIAM L. DAVIS AND ROBERT WHYTE, OF LANSING, MICHIGAN, ASSIGNORS TO- Patented Jan. 14, 1930 NITE'D GENERAL MOTORS CORPORATION, OF DETROIT, MICHIGAN, A GORIPORATION OF DELAWARE THERMOSTATIC VALVE WITH BY-Ii'ASS Application filed March 9, 1928. Serial No. 260,495.

This invention relates to internal combustion engines of the water cooled type, and more particularly to an improved arrangement for controlling the circulation of cooling medium theret-hrough.

One of the objects of the invention is to provide a thermo-sensitive element at the outlet from the engine cylinder, which carries a pair of valves controlling respectively, an outlet leading to a cooling radiator, and a by-pass around the radiator leading directly to the water pump, thereby affording a continuous circulation thru the engine jacket atall times and reducing resistance to the operation of the pump.

The structure forming thesubject matter of the invention, is intended to eliminate circulation through the radiator when the engine is first started and the cooling liquid is cold, so that the engine will warm up quickly to an eflicient operating temperature. As the engine warms up. the thermo-sensitive element causes the valve over the outlet to in the accompanying the radiator-to move away from its seat, and

the valve for the by-pass to move toward its seat, allowing circulation through the radiator and restricting the flow through .the bypass, until the liquid reaches a temperature calling for the full circulation through the cooling radiator, when the outlet valve will be entirely open and the by-pass'valve held tightly on its seat.

A preferred, but not necessarily the only embodiment of the invention, is illustrated drawing wherein 1 is a fragmentary si e elevation of an engine and radiator associatedtherewith.

Fig. 2 is a view of the upper and front portion of the engine wlth parts shown 1n section.

Fig. 3 is a detail side elevation of the thermostat control unit.

Fig. 4 is a section taken on line Fig. 3 and v Fig. 5 is a section taken on line 5-5 of Fi 2. y

l ieferring to the drawings, the reference character 1; indicates the usual hgat radiating unit forming a' part of the c rpulatory system, the .outlet of which is connected with a suitable pump operated from the engine crankshaft, for withdrawing the cooled water, or other cooling medium, from the radiator, and sending it through the engine jacket in the cylinderblock 2 and head 3. At the upper front portion of the jacketed cylinder head 3. an upwardly extending tubular portion 4- is provided, into which is screwthreaded a plug 5, having an outlet leading directly to the pump, and the cylinder head 3 has an integral hollow boss or raised portion 10, extending upwardly into the jacket and having an opening 11 in alignment with the outlet passageway 6.

Interposed between the raised boss and the block 5, is a thermo-sensitive element which controls the liquid flow through the respective passageways 6 and 9 in accordance with temperature conditions. In the present case, this thermo-sensiti've element is of the well known bellows type, indicated at 12, and which expands as the temperature rises and contracts as the temperature falls.

The upper end of the thermostat bellows 12 is held in a fixed position by a fastening stud or pin 13, having a screw threaded extremity forengagement within the hub 14, carried at the end of the passageway 6 by a number of radially extending webs or arms 15, integral with the plug 5. Secured as by a rivet 16, to the opposite end of the thermostat bellows, is a valve element, which for convenience and economy of manufacture may be stamped from sheet metal, and which comprises a disk or plate 17, having a pair of oppositely disposed arms 18 extending upwardly and carrying at their upper ends, a

plate or disk 19 having a central opening therein through which the stud 13 projects, and an annular flange 20 for sliding engagement on the shank of the stud.

When the thermostat bellows is contracted the disk 19 seats against the adjacent face of the plug 5 closing the outlet flpassageway 6. At such time, all the cooling u1d Wlll enter the opening 11 and flow through theby-pass 9 to the amp, insuring continuous circulation throng the engine jacket at all times. Since the flow through the radiator is cut off, there will be no dissipation of heat, whereby the engine will heat up rapidl ts the temperature rises to a point whic enables the engine to operate most efliciently, the action of the heat of the thermostat causes the expansion thereof, which carries alon the valve element to move the valve disk 19 0 its seat and allow some of the heated water to pass to the radiator, and also moves the valve disk 17 toward it seat, so as to restrict the flow through the by-pass. The pump, therefore, draws some of the cooled liquid from the radiator which, in the same manner, warms up as it absorbs the heat of the explosions. When the fluid throughout the entire system reaches the temperature necessitating its complete passage through the radiator to prevent overheating of the engine, the expansion of the bellows will have caused the valve to move to the dotted line position in Fig. 2, at which time the valve disk 17 will be seated tightl against the face of the boss 10 cutting off a l circulation throu h the by-pass and causing all the liquid to ifow through the outlet passa e 6.

aving thus described our invention we claim:

1. In an internal combustion engine, the combination with a water jacketed cylinder head having an outlet 0 ening therein, and a rai d boss integral with the head having an passages and a pair of valves carried by said element beyond the opposite ends thereof controlling the flow from the jacket through the respective outlet passages.

4. In an internal combustion engine, the combination with a water jacketed cylinder head havin aligned openings in the top and bottom wal s, and of a fluid flow control unit including a plug insertable within one of said openings and aving a passage therein in a ignment with the other of said openings, a thermo-sensitive element carried by said plug intermediate the sage and the last mentioned opening, an a pair of valves positioned beyond opposite ends of and carried by said element for closing one or the other of the last mentioned 0 enings and the passage in accordance with thermal conditions.

5. In aninternal combustion engine, the combination with a water jacketed cylinder head having an opening therein, an integral boss formin a valve seat and having an opening therein eading to an outlet passageway, of a plug fittin into said cylinder head opening, one end 0 which forms a. valve seat for an outlet passageway therethrough in alignment with the first mentioned passageway, a thermo-sensitive element having one end fixed to saidplug, a valve member fixed to the opposite end of said element, and movable upon operation thereof, and having one portion adapted to seat against the boss under hot conditions of the engine, and another portion ada ted to seat against the plug under cold con itions of the engine.

In testimony whereof we aflix our signatures.

WM. L. DAVIS. ROBERT WHYTE.

out et port spaced from and aligned with said outlet openin of a lug fitted into the outlet opening an providbd with a .passa eway, a thermo-sensitive element carried y said plug and positioned between the plug and said boss, and valve members carried by said element and positioned beyond opposite ends thereof for controlling fluid flow through said passageway and said outlet port respectively.

2. In an internal combustion engine, the COIl'lb1l'lltl()ll with a water jacketed cylinder head having a pair of aligned outlet openings therein arranged face to face in spaced relation, of a valve member having portions at opposite ends thereof adapted to seat over said openin s, and a thermo-sensitive element interposed between said openings and connected with said valve member for controllin the movement of said end portions to and from their seats in inverse unison relation.

3. In an internal combustion engine, the combination with a water jacket, a pair of aligned outlet passages leading in opposite directions from said jacket, a thermo-sensitive element interposed between said outlet 

